Dorthe Bleses

Strong evidence ties early language difficulties to later adjustment challenges. Little is known, however, about factors that exacerbate these associations. The present study tests the hypothesis that unsupervised, solitary screen time amplifies longitudinal associations from low language skills to heightened socioemotional difficulties. The participants were 546 (264 girls, 282 boys) 4–5-year-olds attending 24 population-based childcare centers in 13 municipalities across Denmark. Teachers twice completed assessments of child adjustment difficulties (i.e., conduct problems and emotional problems), approximately six months apart. At the outset, teachers assayed child language abilities (i.e., communication skills and productive vocabulary) and parents reported solitary screen time (i.e., the amount of time children spent alone viewing handheld devices or television). Results indicated that solitary screen time and low communication skills predicted increases in subsequent emotional problems. Moderated associations emerged for conduct problems, such that solitary screen time exacerbated longitudinal associations from oral language problems to later adjustment difficulties. Specifically, among those with above (but not below) average levels of solitary screen time, low initial productive vocabulary and low initial communication skills predicted increases in conduct problems across the course of six months within a single school year.

We Learn Together is a 20-week, low-cost infant/toddler school-readiness intervention developed to provide instructional content and supportive tools for teachers to be more explicit and intentional in interactions with children to support early development. Short-term effects were established in a previously published real-world effectiveness randomized controlled trial. In the present quasi-experimental study, we examined the extent to which the effects remained approximately 1 year after the intervention. Because the original control group eventually also got the intervention, we compared mandatory municipal language assessment outcomes of 2,327 children in the treatment group to matched nontreatment children. The intervention effect was maintained at similar magnitudes at the 1-year follow-up for oral language skills (effect sizes = 0.09–0.14), and spillover effects were found for rhyming skills (effect size = 0.12).

Objective: Maternal thyroid autoimmunity and thyroid function in early pregnancy may impact fetal neurodevelopment. We aimed to investigate how thyroid autoimmunity and thyroid function in early pregnancy were associated with language acquisition in offspring at 12–36 months of age. Methods: This study was embedded in the prospective Odense child cohort. Mother–child dyads were excluded in case of maternal intake of thyroid medication during pregnancy. The parents completed MacArthur–Bates Communicative Development Inventories (MB-CDI) every third month to assess their offspring’s productive vocabulary. All completed reports for each child were included in the analyses. Logistic growth curve models evaluated associations between MB-CDI scores and levels of maternal thyroid peroxidase antibodies (TPOAb), free thyroxine (FT4), and thyrotropin, respectively, measured in early pregnancy (median gestational week 12). All models were stratified by offspring sex and adjusted for maternal age, education, pre-pregnancy body mass index, parity, breastfeeding, and offspring age. Results: The study included 735 mother–child dyads. Children born to mothers with TPOAb ≥11 kIU/L, opposed to TPOAb P < 0.001) and 33–36 months for boys (OR = 0.83, P < 0.001). The probability of producing words was higher in girls at 30–36 months of age with low-normal maternal FT4 vs high-normal FT4 (OR = 0.60, P < 0.001), and a similar trend was seen in boys. Results were ambiguous for thyrotropin. Conclusion: In women without known thyroid disease, TPOAb positivity in early pregnancy was negatively associated with productive vocabulary acquisition in girls and boys. This association was not mediated by a decreased thyroid function, as low-normal maternal FT4, unexpectedly, indicated better vocabulary acquisition. Our results support that maternal thyroid autoimmunity per se may affect fetal neurodevelopment.

There are well-documented associations between numeracy development in preschool age children and general and math vocabulary, literacy, and executive functions. However, the studies have largely included small samples of children with parents with either predominantly low or higher socioeconomic background (SES); further, few studies have included measures of all these domains in the same analyses. In this current study, we examined how general vocabulary, math vocabulary, rhyme detection and three measures of executive functions are associated with numeracy development in a population representative sample of 2,931 Danish children 3–5 years (51% male, 89% white). Multi-level regressions controlling for child age and, sex, and in some analyses also parental education and income confirmed that general vocabulary (β = 0.16), math language (β = 0.17), rhyme detection (β = 0.14), attention shifting (β = 0.09), inhibitory control (β = 0.05), and working memory (β = 0.09) each are associated with numeracy after controlling for covariates when estimated in the same model. Analyses of extreme performance (low-high) suggests a much closer and symmetrical connection between math language and numeracy compared to that between general vocabulary and numeracy. Interestingly, family SES is weakly but significantly related to all measures, most strongly for the vocabulary measures, but does not influence the pattern of results from regression analyses. In conclusion, both general vocabulary and mathematics-specific vocabulary contribute substantially to early numeracy skills. Rhyme detection and executive functions are also associated with numeracy skills, but with a lower magnitude.

Using Danish administrative data, we address the issue of efficient targeting in childhood interventions. We define children to be in need of an intervention if they experience one or more socially undesirable outcomes in adulthood. Because interventions are very effective early in life, we then test if and to what extent indicators available at birth can predict these outcomes. We find fair to good levels of prediction accuracy for many outcomes, driven by a parsimonious set of predictors. We show that optimal weights for the construction of risk scores deviate from the weights typically used in targeted interventions.

Language development during early childhood is considered an important marker of fetal neurodevelopment. Prenatal cortisol exposure plays a critical role in maturation of the fetal brain; however, the effect on offspring language development needs further investigation. In this prospective observational study we aimed to evaluate the association between maternal third trimester cortisol and early longitudinal offspring language development in the Odense Child Cohort (OCC) and to test whether there were sex differences in the association. The study cohort included 1093 mother–child dyads (570 boys and 523 girls). Fasting morning serum (s‐) cortisol was collected from third trimester (gestational week 26–28) pregnant women and measured by liquid chromatography–tandem mass spectrometry. Offspring receptive and productive vocabulary assessments by MacArthur‐Bates Communicative Development Inventories parent reports were completed every third month from children age 12–37 months. Levels of cortisol were higher in women carrying a girl (858 ± 214 nmol/L) than in women carrying a boy (820 ± 222 nmol/L). Higher third trimester maternal cortisol levels showed a positive association with development of productive vocabulary in boys at age 12–21 months (OR = 1.23, SE = 0.07, p = .005) and age 22–37 months (OR = 1.09, SE = 0.06, p = .967). Higher maternal cortisol levels in the third trimester were positively associated with receptive vocabulary in girls at 12–21 months of age (OR = 1.16, SE = 0.05, p = .002). Maternal third trimester s‐cortisol levels were positively associated with early language development in children at age 12–37 months.

Measurement error is a ubiquitous element of social science studies. In large-scale effectiveness intervention studies on child language, administration of the assessment of language and preliteracy outcomes by speech and language pathologists is costly in money and human resources. Alternatively, daycare educators can administer the assessment, which preserves considerable resources but may increase the measurement error. Using data from two nationwide child language intervention studies in Denmark, this article evaluates daycare educators’ measurement error when administering a test of language and preliteracy skills of 3 to 5 year old children that in part is used in a national screening program. Since children were randomly assigned to educators, hierarchical linear models can estimate the amount of additional measurement error caused by educators’ language assessments. The result shows that the amount of additional measurement error varied between different language subscales, ranging from 4% to 19%, which can be compensated for by increasing the sample size by the latter percentage. The benefits and risks of having daycare educators administer language assessments are discussed.

Predictive relations between language and literacy skills during the preschool years and children’s future reading achievement are well-documented, leading to development and evaluation of preschool interventions targeting early skill development. Although educational researchers have developed and found some positive short- and mid-term effects of language and literacy intervention supplements implemented in early childhood education (ECE) settings, fade-out is a concern. Most studies have targeted children experiencing risk, rather than a more representative sample. Additionally, there are very few studies of long-term intervention effects, and heterogeneity of long-term effects has not been well described. In the present study, we build on initial reports of one of the largest studies of a language and literacy intervention supplement, the SPELL randomized controlled trial implemented as part of the universal ECE system in Denmark. SPELL was delivered to an unselected sample of children at 3–5 years of age (n =7,076). Results of the base intervention (SPELL) and two enhanced versions featuring extended professional development for teachers (SPELL+PD) or an add-on home-based program for parents (SPELL+HOME) showed short-term effects for literacy outcomes for all children for all SPELL conditions compared to business as usual (BAU). In this follow-up study, we utilized follow-up assessments of 2,700 SPELL 4-5-year-old participants with national reading tests in second grade. The main analyses based on the whole sample showed no significant differences in reading scores in second grade for those in any of the three SPELL conditions relative to the BAU condition. However, moderation analyses demonstrated heterogeneity in intervention effects with children whose mothers had low-mid education showing sustained and mostly large-sized effects. Other risk factors, including income and immigrant background, and condition interacted with at least one outcome variables. These findings suggest that at-risk children in some cases derive long-term benefits from early language and literacy intervention enhancing learning opportunities in ECE settings.